At the present time, patients with well differentiated thyroid cancer who have undergone a near total thyroidectomy are frequently subjected to a total body I131 scan and I131 treatment if thyroid remnants and/or metastasis are identified on the scan. Prior to these treatments, the standard of care requires withrawal of thyroid hormone replacement to stimulate endogenous TSH secretion needed to optimize I131 uptake by residual thyroid tissue and/or metastasis. This approarch may be hazardous in patients with medical consitions such as congestive heart failures, which may be adversely affected by a prolonged state of hypothyroidism. The purpose of this study is to offer patients with thyroid cancer an injection of recombinent TSH (Thyrogen) to avoid prolonged hypothyroidism prior to obtaining a thyroid scan for the direction and treatment of residual thyroid cancer. As a product of recombinent technology, Thryrogen could support TSH-dependent metabolic activities without being recognized as an antigenic entity. Until now, two patients have been successfully treated with thyrogen according to this protocol. Neither experienced any adverse reaction and in both thyrogen administration allowed visualization of residual and/or metastatic thyroid tissue on total body scan and treatment with I131.